P41 STEERING TO T8

  Lau Gatignon / SL-EA

Note : all currents are for 450 GeV/c

The optics is the same for proton and ion operation.


HORIZONTAL PLANE

1. Steering through TAX(7) and TAX(8)

Select a small hole in TAX(8), e.g. by SET TAXMOT(8)=100
Scan Bend-1 onto TRIG1 with steps of 9.1 Amps/mm

2. Correct for horizontal angle in TAXMOT(7) and TAXMOT(8)

   At TAX(7)+(8)               BEND-2H                   BEND-3H           
         x1             R12 = -3.63 mm/mrad        R13 = -10.61 mm/mrad    
        x'1             R22 = 1.0  mrad/mrad       R23 = 1.0 mrad/mrad

Steer angle at TAX:

0 = 3.63 theta2 -10.61 (1-theta2) -> theta2 = -1.52 mrad/mrad
0 = 3.63 (1-theta3) - 10.61 theta3-> theta3 = -0.52 mrad/mrad

Tune with linear combination B2 - 0.3421 B3 to give 1 mrad for B2 = 2.28 Tm and B3 = -0.78 Tm

3. Steering through COLLS 1 and 3

Use a linear combination of BEND2 and BEND5

                               COLL 1                     COLL 3           
       BEND-2              20.552 mm/mrad            -222.82 mm/mrad       
       BEND-5              46.460 mm/mrad            -154.50 mm/mrad

hence

       Bends                   COLL 1                     COLL 3           
       BEND-5               46.46 mm/mrad               don't care         
   B2 - 1.4422 B5          -47.712 mm/mrad                  0              
   B2 - 0.4406 B5                 0                  -154.749 mm/mrad

4. Steering through COLL-5

Scan BEND-7 through a small slit in COLL-5 onto TRIG-1. Sensitivity 0.28 Amps/mm

5. Steering towards Fiscs at T8

Scan through Q20 aperture with BEND-8, sensitivity 1.0 Amps/mm.
Center at T8-Fiscs with TRIM-10, sensitivity 6.3 Amps/mm


VERTICAL PLANE

6. Position of TAX(7) and TAX(8)

Study transmission as a function of TAXMOT(8) position. Choose position with optimal transmission.
TAXMOT(7) and TAXMOT(8) have shown good relative alignment.

7. Steering through COLLs 2 and 4

                               COLL 2                     COLL 4           
       TRIM-1              -412.75 mm/mrad           -17.181 mm/mrad       
       TRIM-4                59.68 mm/mrad             43.91 mm/mrad

hence

       Trims                   COLL 2                     COLL 4           
       TRIM-1              -412.75 mm/mrad              don't care         
  TR1 + 0.3912 TR4         -389.4 mm/mrad                   0              
  TR1 + 6.9162 TR4                0                   291.5 mm/mrad

8. Steering through COLL-6

Scan TRIM-6 through a small slit in COLL-6 onto TRIG-1. Sensitivity 4.7 Amps/mm

9. Steering towards Fiscs at T8

Scan through Q19 aperture (-> angle at T8) with TRIM-6 and TRIM-7

                       COLL-6                 Q19          T8                   
    TRIM-6          115.03 mm/mr          -354.1mm/mr      9.87 mm/mrad         
    TRIM-7           66.78 mm/mr           -378.0 mm/mr      -10.17 mm/mrad

TR6 - 1.7225 TR7 gives 297 mm/mrad at Q19, 27 mm/mrad at T8, 0 mm at COLL6.

Then steer to T8 Fisc with BEND-10, sensitivity 4 Amps/mm

Last updated : 26 July 1996 by Lau Gatignon